During tonight's 12-12-12 Concert for Sandy Relief at New York City's Madison Square Garden, some amazing, you-had-to-be-there pairings took place on the venue's historic stage. Case in point: Roger Waters of Pink Floyd fame performing 'Comfortably Numb' with Pearl Jam singer Eddie Vedder.

Vedder lent his vibrato to the song's choruses, adding his signature style to the Floyd classic. It was a haunting performance, one that will stay with viewers for days. Vedder and Waters did not interact much, but they didn't need to. Their voices did all the work, and their chemistry as two legendary rock artists meshed perfectly. Better still, it was for a good cause.

Vedder sang the song like he wrote it, his emotive voice adding another layer of power and heft to the song's already weighty lyrics.

It's rare that two generations of rockers of this caliber collide onstage, so when it does happen, it's bound to be special. Vedder and Waters didn't disappoint, and you can relive their visceral performance below.